Rolls of light sensitive paper and film require light-tight packaging so that they are not exposed to daylight prior to use. However, the rolls should be packaged such that they can be loaded into co-operating apparatus under daylight conditions. Furthermore, the packaging must not adversely affect the ease of rotation of the roll during unwinding and must not interfere with the roll if the web is rewound back onto the roll.
U.S. Pat. No. 5,133,171 discloses a package which includes a pair of opaque flexible end discs attached to the ends of the core of the roll of material and an opaque leader attached to the leading end of the length of material forming the roll. After a first convolution of the leader is wrapped onto the roll peripheral portions of each end disc are folded over the first convolution. A second convolution is then wrapped onto the roll to capture the folded over portions between the first and second convolutions of the leader. No adhesive is used, friction being relied upon to hold the folded over portions between the convolutions.
U.S. Pat. No. 5,515,970 discloses a package having similar opaque end discs and leader. In this case the folded over portions of the end discs are held in place by adhesive tape strips.
U.S. Pat. No. 5,655,659 discloses a package having an opaque leader wound around the roll. Folded over portions of the end discs have radially arranged perforations and are held in place by adhesive tape strips.
In the above packages the end discs tear circumferentially at the edge of the roll when the leader is pulled. The perforations are provided to aid in initiating a tear. Sometimes when the package is opened this tear deviates from the preferred direction. This unsatisfactory tear can result in part of the outer diameter remaining untorn and forming "ears." These ears impede the rewinding of the roll. Unsatisfactory tearing can also lead to entry of light into the package and fogging of the light sensitive material.
The end discs of the light-tight package must be tearable when the leader is pulled. However it is a requirement that the disc tears circumferentially in such a way that no ears remain to impede rewinding of the package. The invention therefore aims to provide a light-tight package having end discs, the outer portions of which will tear in a more controlled manner when the leader is pulled such that any ears that do remain do not interfere with rewinding of the package.